For surface cleaning it has long been a desire to combine cleaning compositions, such as detergents or scouring fluids, with a substrate, such that a user does not need to add such a composition for easing the work and/or optimizing the amount of used compositions. The prior art as well as commercial products show two main approaches.
A first approach employs one-time usage substrates, which may be of particular composition, such as micro-fibres, or may be particularly treated, such as antistatically. They may also comprise additives, such as cleaning compositions, and are delivered to the user in a dry or in a wet state. It is also known to deliver essentially dry (“dry to the touch”) substrates, which can be wetted, such as with water, for the cleaning. Upon cleaning, the substrate is loaded with dirt, and discarded once the additive is exhausted and/or the dirt level reaches a critical level.
Such systems not only have the disadvantage that they are inefficient in the use of substrate, which is undesirable both from an economical as well as an ecological point of view. Also, such systems require special precautions with regard to storing and distributing the substrates, particularly if these are wet and thusly are prone to microbial contamination.
JP-A-2 047 397 relates to paper containing soap in its fiber tissues. U.S. Pat. No. 4,935,158 describes a (non-washable) cleaning pad comprising a solid detergent cleaning composition, which is reusable by means of a slow release of the active agent constituents.
The other conventional approach employs re-usable substrates, which are washed and dried and delivered to the cleaning location. There, they may be used as such, as well known for microfiber substrates. Alternatively, a cleaning liquor is prepared, often by adding a cleaning composition to water such as in a bucket with a squeezing insert. A further alternative uses cleaning implements which comprise a dosing unit, such as may be fixed to the handle of the cleaning implement, and which is used to deliver the cleaning liquor to the cleaning surface or substrate.
Such systems typically require that the cleaning liquor is prepared at the cleaning location, which often results in misdosage of the cleaning composition and/or of the water, which may result in unsatisfactory cleaning results, such as poor dirty pick-up and/or streaking, and which, in the case of overdosing, may deteriorate economics. In particular for professional cleaning, the use of larger containers for the cleaning composition may lead to complications in the logistics chain or on site. Further a significant portion of the cleaning composition is discarded with the cleaning liquor after use.
EP-A-0 153 146 relates to an article suitable for wiping surfaces including a substrate which can carry the detergent that is delivered to the surface during wiping. U.S. Pat. No. 4,014,808 describes a detergent formulation useful in aqueous working solution for the treatment of soiled floor surfaces. Other wiping articles and the like have been described, for example, in GB No. 1 522 759 (Airwick); EP 66 463A (Unilever); EP No. 68 830A (Unilever); GB No. 1 326 080 (Freudenberg); and GB No. 1 304 375 (L'Oreal). Therein, the active material (liquid or solid but usually liquid) is generally encapsulated or compartmented in some way and can be released only by the application of some stimulus, for example, squeezing, rubbing or wetting.
However, none of the publications addresses the problem of providing washable and re-usable substrates, which are essentially dry and which are preloaded with a cleaning composition for being wetted upon use. Also, there is no disclosure of loading a washable substrate with a cleaning composition during or after washing and subsequently storing and/or transporting it in a dry state to the cleaning location.
Thus, in one aspect the present invention addresses the remaining problems by providing a re-usable and washable substrate, which has been loaded with suitable cleaning substances but which can be stored and transported in an essentially dry state. In another aspect, the present invention relates to the method of preparing such a loaded, essentially dry substrate, and in a further aspect to a method for cleaning a surface, whereby a substrate is used, which is washed after being used and dirt loaded and loaded with a cleaning composition thereafter, such that it can be stored and/or relocated to the cleaning location, where it is combined with a cleaning carrier, such as water.